HI Flow Cats - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

anth331 · 09-20-2018, 08:48 AM

Do Hi Flow Cats really give you any more horsepower or, just make it louder?
I have a 13 SS L99 was thinking about buying some.

Pete G · 09-20-2018, 09:09 AM

you talking about compared to stock Cats?
Stockers are said to be restrictive but I could not give you a # in terms of HP

anth331 · 09-20-2018, 10:35 AM

I've heard 5 to 10 hp. That little hp for 400 to 700 dollars isn't worth it to me.

zz430camaro · 09-20-2018, 10:41 AM

Quote:

Originally Posted by anth331

I've heard 5 to 10 hp. That little hp for 400 to 700 dollars isn't worth it to me.

There is no way a catalytic converter will increase the power. They usually make the exhaust system quieter.

GodWentPunk · 09-20-2018, 11:45 AM

I plan to get hi-flow cats next year when I get my headers done.

joe...

mpsgolf · 09-20-2018, 11:55 AM

Their claim to fame is more power and sound.

You will get debates all day long as to how much power.

I had a pair of HFCs for a while. I already had SW retro cat back. I got a little more volume and better tone. But I wanted a deeper rumble snd a bit mote volume. I added JBA shorties and HFCs. It was louder for sure. I didnt like the tone or drone at some RPMs so I ditched the HFCs and now I like the volume and tone. I likely like it a little milder than some.

I never had a dyno so couldnt give you hp facts. I plan to get a tune so will have before and after data one day.

rontammy0 · 09-20-2018, 12:34 PM

Quote:

Originally Posted by zz430camaro

There is no way a catalytic converter will increase the power. They usually make the exhaust system quieter.

Wrong on both accounts...

HyperV117 · 09-20-2018, 12:38 PM

I've heard that the stock cats actually flow pretty well. The only reason I have them is because the guy I bought my LTH's bundled them in. Otherwise I might have just gone with offroad pipes.

InFiD3ViL · 09-20-2018, 05:01 PM

Quote:

Originally Posted by anth331

I've heard 5 to 10 hp. That little hp for 400 to 700 dollars isn't worth it to me.

If you are chasing horsepower, you are going to wish that 5-10 hp only cost you $400-700.

In the beginning of the mods, HP is at its cheapest. Also keep in mind, all these mods we do add up.

Quote:

Originally Posted by zz430camaro

There is no way a catalytic converter will increase the power. They usually make the exhaust system quieter.

Are you thinking of adding to a car with no cats? That's the only situation that you make sense. Removing the restrictive stock cats and replacing with high-flows will certainly free up some HP....and beautiful noise.

anth331 · 09-20-2018, 05:27 PM

All I have so far in mods 2 3/4 BBK X pipe exhaust with Borla S type mufflers and a dry hi flow air filter, that’s it

zz430camaro · 09-20-2018, 06:06 PM

Quote:

Originally Posted by InFiD3ViL

If you are chasing horsepower, you are going to wish that 5-10 hp only cost you $400-700.

In the beginning of the mods, HP is at its cheapest. Also keep in mind, all these mods we do add up.

Are you thinking of adding to a car with no cats? That's the only situation that you make sense. Removing the restrictive stock cats and replacing with high-flows will certainly free up some HP....and beautiful noise.

Ya, I thought he had headers and no cats when I said that. Not used to people doing modifications with the stock manifolds and cats in place. Sorry for the confusion.

What he really needs to do is get headers and high flow cats. There is someone right now selling headers and cats in the classified section here.

anth331 · 09-20-2018, 06:18 PM

I’m thinking of either getting headers and the high flow cats or just getting the 3.91 gear swop I can only do one

Talladega · 09-20-2018, 06:31 PM

Quote:

Originally Posted by anth331

I’m thinking of either getting headers and the high flow cats or just getting the 3.91 gear swop I can only do one

I have done both mods and can say with no doubt do the gears first. Absolutly the best bang for your buck if you can do only one.

antman · 09-21-2018, 09:50 PM

Quote:

Originally Posted by anth331

Do Hi Flow Cats really give you any more horsepower or, just make it louder?
I have a 13 SS L99 was thinking about buying some.

I have hi flow cats on my ‘13 L99 on stock exhaust and they made the car louder and gave it more power. I can’t tell how much HP but it was definitely noticeable. The center resonater was then removed and that gave it a little more boost.

09-20-2018, 08:48 AM	#1
anth331 Drives: 12SS Join Date: Apr 2010 Location: Dayton, Tx. 77535 Posts: 728	HI Flow Cats Do Hi Flow Cats really give you any more horsepower or, just make it louder? I have a 13 SS L99 was thinking about buying some.

09-20-2018, 11:45 AM	#5
GodWentPunk Drives: 2015 2SS White Convertible CE/INDY Join Date: Mar 2016 Location: Lockport, IL Posts: 780 View My Garage	I plan to get hi-flow cats next year when I get my headers done. joe... __________________ ARH LTH/HFC/Legato muffler, RDP Custom Tune, K&N Blackhawk CAI, Bigworm Blackout kit, ZL1 Rims, Phantom Grills, VMAX PTB

09-20-2018, 11:55 AM	#6
mpsgolf Drives: 2012 Camaro SS Transformer Join Date: Sep 2013 Location: St Louis Missouri Posts: 501	Their claim to fame is more power and sound. You will get debates all day long as to how much power. I had a pair of HFCs for a while. I already had SW retro cat back. I got a little more volume and better tone. But I wanted a deeper rumble snd a bit mote volume. I added JBA shorties and HFCs. It was louder for sure. I didnt like the tone or drone at some RPMs so I ditched the HFCs and now I like the volume and tone. I likely like it a little milder than some. I never had a dyno so couldnt give you hp facts. I plan to get a tune so will have before and after data one day. __________________ 2012 Camaro SS Transformer Mods: trunk subwoofer and amp, LED lighting (fogs, interior, trunk), skip shift eliminator, CAI cold air kit, Vmax ported throttle body, Stainless Works retro chambered cat back, JBA Cat4ward SS ceramic coated headers Potential Next Mods: Tune, F&R sway bars, rear cradle bushing inserts and trailing arms

09-20-2018, 12:38 PM	#8
HyperV117 Drives: 2010 Camaro 1SS Join Date: Nov 2015 Location: CA Posts: 358	I've heard that the stock cats actually flow pretty well. The only reason I have them is because the guy I bought my LTH's bundled them in. Otherwise I might have just gone with offroad pipes. __________________

09-20-2018, 09:09 AM	#2
Pete G Drives: 2015 SS 1LE Join Date: Sep 2014 Location: Long Island, NY Posts: 252	you talking about compared to stock Cats? Stockers are said to be restrictive but I could not give you a # in terms of HP

09-20-2018, 10:35 AM	#3
anth331 Drives: 12SS Join Date: Apr 2010 Location: Dayton, Tx. 77535 Posts: 728	I've heard 5 to 10 hp. That little hp for 400 to 700 dollars isn't worth it to me.

09-20-2018, 05:27 PM	#10
anth331 Drives: 12SS Join Date: Apr 2010 Location: Dayton, Tx. 77535 Posts: 728	All I have so far in mods 2 3/4 BBK X pipe exhaust with Borla S type mufflers and a dry hi flow air filter, that’s it

09-20-2018, 06:18 PM	#12
anth331 Drives: 12SS Join Date: Apr 2010 Location: Dayton, Tx. 77535 Posts: 728	I’m thinking of either getting headers and the high flow cats or just getting the 3.91 gear swop I can only do one